This invention relates to user registration and location management for mobile telecommunications systems. In particular, it relates to Universal Mobile Telecommunications Service (UMTS) systems, when used to provide connectivity between an IP (Internet Protocol) capable end-device and an IP-based network.
When a UMTS user switches on his mobile terminal (I), the user needs to be registered with the UMTS network. Similarly, when the user moves around the area covered by the network, location management procedures need to take place in order to allow the user to be provided with services.
The initial registration process normally involves requesting for registration on the network, authentication of the user by the network, registration of the user and informing the home location register (HLR) of the users current whereabouts. This takes place at the UMTS level.
At the IP (Internet Protocol) level, there are three scenarios to consider when the user switches on an IP capable terminal. These are:
(1)the user has a static home IP address,(2)the user requires a dynamic home IP address from the UMTSoperator, and(3)the user requires a dynamic home IP address from a body outsidethe UMTS domain.
In any case, a mobile IP registration with the home agent (HA) and perhaps the foreign agent (FA) needs to take place before the user can successfully engage in a data transaction using the Internet Protocol.
The current solution for the registration of data (IP) users in UMTS with mobile IP relies on the use of two, subsequent, registrations, the first at the UMTS level and the second at the IP level. This is shown in FIG. 1.
The user of a mobile terminal switches on his mobile terminal MT1 and requires registration with the UMTS network. He sends a message 2 requesting registration which passes through a radio network controller (RNC) 3 (which may also be the foreign agent (FA) for the IP protocol) to a switching centre with a visiting location register (VLR) 4. This in turn requests user information from any previous visiting location register 5 which the user may have last received service from, or from the user's home location register (HLR) 6. This sends back information concerning the user to the new VLR 4 and then an authentication request 7 and reply 8 are sent to and received from the mobile terminal 1. After this authentication, registration of the mobile terminal is complete and a register complete message 9 is sent to the terminal. Also, a message 10 is sent to the HLR informing the HLR of the new location of the terminal.
If IP registration is also required, then a further IP registration step also has to take place with conventional systems.
Once UMTS registration is complete, the mobile terminal 1 sets up a UMTS data channel 11. The mobile terminal 1 sends an FA router solicitation message 12 to the new RNC/FA 3 and this in turn sends an FA advertisement 13 back to the mobile terminal over the data channel. The mobile terminal then sends a registration request which passes through the RNC/FA 3 and onwards to the home agent 14. This then sends back a registration reply 15 to the mobile terminal and IP registration is complete. The foreign agent FA in IP is analogous to the VLR (visiting location register) in the UMTS domain.
Accordingly, two independent registration processes are necessary, first the UMTS registration and then the IP registration.
When a UMTS user moves around the area covered by the network, location management procedures need to take place in order to allow the user to be provided with services. Location management under a single radio network controller (RNC) does not affect the IP level. However, inter-RNC location updates have to involve IP level mobility as well as UMTS mobility. This is because it is assumed that mobile IP foreign agents (FA's) and RNC's are co-located.
Conventionally, an analogous process to the conventional method of registration has been done. Firstly UMTS location update is done and then, independently, a subsequent IP location update is done. This is shown in FIG. 2.
The location update procedures are similar in principle to the registration updates of FIG. 1, except that the location update 16 is required for both IP and UMTS, rather than register updates. Apart from this, the procedures involve similar steps, mutatis mutandis.
In both the user registration and location management scenarios, the complete separation of the two procedures for UMTS and IP bring inefficiencies in the usage of the air-interface, and delays to the overall registration or location update procedure.
The present invention arose in an attempt to reduce these inefficiencies and to reduce the time taken for the overall registration procedure or for the overall location update procedure.
It is known from the paper by Clapton A J et al entitled “UMTS—the mobile part of broadband communications for the next century”, BT Technical Journal, GB, BT Laboratories, vol. 16, no. 2, 1 Apr. 1998, pages 120–131, XP000750524 ISSN=1358−3948 to provide a method for a mobile terminal in a UMTS and IP telecommunications network to register and/or update its location.